Acute Lymphocytic Leukemia (ALL) or Acute Lymphoblastic Leukemia is a cancer of the white blood cells. Learn more about symptoms and treatment. READ MORE
Addison disease, or primary adrenal insufficiency, happens when your adrenal glands don't make enough of certain hormones. Learn about symptoms and treatment. READ MORE
An allergy is a reaction by your immune system. Substances that cause reactions include pollen and food. Find the full list of allergies and symptoms. READ MORE
Anaphylaxis or anaphylactic shock is a serious allergic reaction. It can begin very quickly, and symptoms may be life-threatening. Read the symptoms. READ MORE
Wild animals might attack if they are threatened or acting protective. Attacks by pets are more common. Learn how to avoid both types of animal bites. READ MORE
Ankylosing spondylitis is a type of arthritis. It causes inflammation between vertebrae and in the joints between spine and pelvis. Learn more. READ MORE
Aplastic anemia is a rare but serious blood disorder. If you have it, your bone marrow doesn't make enough new blood cells. Read more on the causes. READ MORE
Asthma is a chronic lung disease. It causes asthma attacks, which make your airways inflamed and narrowed, and your lungs get less air. Learn about treatments. READ MORE
Autoimmune diseases are where your immune system attacks healthy cells in your body by mistake. Learn about the symptoms, tests, and treatments. READ MORE
Bone marrow transplantation replaces faulty bone marrow with healthy bone marrow from a donor. Learn about the possible risks, and procedure. READ MORE